Vibratory finishing apparatus



0, .1970 BA. mew: 3,490;.1s1

VIBRATORY FINISHING APIARATIUS Original Filed April 17, '19s? gsheetksheet 1 a? &\\\\\\\\\\\\\\ a oV////J///l//j/ INVENTOR.

Jan. 20, 1970 B. A. RACINE VIBRATORY FINISHING APPARATUS 2 Sheets-Sheet 8 Original Filed April 17, 1967 Ema INVENTOR.

BY f 6 J'TOE/I/FJ/ United States Patent cc 3,490,181 VIBRATORY FINISHING APPARATUS Bill A. Racine, Hacienda Heights, Calif., assignor to Sweco, Inc., Los Angeles, Calif., a corporation of California Continuation of application Ser. No. 631,466, Apr. 17, 1967. This application Mar. 10, 1969, Ser. No. 809,467 Int. Cl. B24b 31/06 US. Cl. 51-163 4 Claims ABSTRACT OF THE DISCLOSURE This application is a continuation of Ser. No. 631,466 filed Apr. 17, 1967, now abandoned.

This invention relates to vibratory grinding, finishing and deburring mills in which the material to be operated on is contacted with a finishing or grinding media in a vibrating environment. More particularly, this application relates to a toroidal bowl vibratory finishing mill having a vertical dam or weir which is movably mounted in the toroid and means for insuring that the weir will remain in its intended position and will easily move within the mill chamber.

Toroidal bowl vibratory finishing vessels in which a charge of relatively adbrasive media is caused to operate on a part to be finished are known in the art and illustrated, for example, by US. Patents 3,100,088; 3,266,739 and 2,268,177. It has been suggested to interpose a vertical dam or weir across a radius of the finishing chamber to both control the motion of parts and media in the mill and to aid in the discharge of parts and media by elevating them to an upper portion of the mill. This concept is disclosed in a patent application filed concurrently with the present application in the name of John R. Strorn which application is based in part on an application made in Great Britain on May 4, 1966, bearing application Ser. No. 19,653/ 66 and entitled Vertical Dam.

In the design of a vertical dam or weir for the use in conjunction with the torodial bowl, it is desirable to make provision for the weir or dam to retract out of position through the bottom portion of the mill chamber and yet insure that the weir will be free to move up and down when desired. It has been found in practice that moving the vertical weir upward and downward becomes increasingly difiicult after the mill is in operation because, during the finishing operation, fine particles of degraded media and material removed from the parts being finished tend to clog any channel or trackway which is provided for guiding the movement of the weir. In addition, it has been found that means must be provided to positively retain the weir in an upright position be cause of the mass pressure created by precessive motion of the parts and media around the mill during the finishing operation. Because of the motion of the mill, the weir member is subjected to a considerable bending moment due to the force of parts and media on the upscreen side thereof.

It is therefore an object of this invention to provide a vertical weir configuration in a toroidal bowl finishing mill which allows the weir to be readily moved upward and downward in the mill.

3,490,181 Patented Jan. 20, 1970 It is another object of this invention to provide a means for positively retaining a vertical weir in a toroidal bowl finishing mill during the finishing and unloading operation.

As described in the above-referred-to J. R. Strom patent application, the purpose of the vertical Weir is to control the mass movement of the parts and media during processing and to provide an automated means for unloading the charge of parts and media from the mill so that the parts can be separated from the media and the media returned to the mill. This is accomplished by providing a screen in conjunction with the vertical weir so that when the weir is in its uppermost position, the charge of parts and media will be forced, by the vibratory action of the mill, to climb up the weir and spill onto the screen. The screen has a mesh size opening such that the media will fall therethrough and return to the mill and the parts will be retained. The vibratory action of the mill causes the parts to move across the screen and discharge from the mill.

In the drawings accompanying this specification:

FIGURE 1 is a partial plan view, partially in phantom, of a toroidal bowl finishing mill having a vertical weir;

FIGURE 2 is a cross section through the line 22 of FIGURE 1 showing the leading edge of the vertical weir in cross section;

FIGURE 3 is a fragmentary cross section view of the vertical weir through the line 33 in FIGURE 1 showing a cross section of the central portion of the weir;

FIGURE 4 is a cross section in fragment through the line 44 of FIGURE 3 illustrating the detail of a portion of the weir configuration;

FIGURE 5 illustrates the construction detail of an upper edge of the Weir; and

FIGURE 6 is an overall view, in cross section, of a mill embodying the invention.

The above and other objects of this invention are accomplished by a vibratory apparatus for finishing, polishing, deburring or grinding which comprises a base, a container for receiving media and parts to be finished, the container forming a generally toroidal channel, means for resiliently mounting the container on the base, vibratory means for imparting relatively high frequency vibrations to the container, weir means associated with the container and arranged generally perpendicular to the channel, the weir means being retractable through the bottom of the channel in a slot provided therein, the weir having a generally flat upper edge and arcuate ends so that only the edges of the ends contact the inner surface of the chamber, the weir further being provided with upwardly depending resilient ear portions for wiping against the inner portion of the channel, the channel being further provided with curb members at the downstream portion of the weir to hold the Weir in its vertical alignment against pressure from the charge of parts and media while the apparatus is subjected to vibration.

Referring now to FIGURE 6, there is illustrated a toroidal bowl finishing mill which consists of a circular base 101 having a lip 102 projecting from the upper portion thereof. Around the lip are mounted a ring of springs 103. Supported on the ring of springs 103, is the toroidal finishing bowl assembly which has a lower donut-shaped supporting plate 104 which is attached to the ring of springs and a generally circular center column 105 which projects below the lower plate 104 to form a well for attachment of the motor 106. Gusset plates 107 are formed to support the entire assembly and center column and are positioned between the springs. The toroidal chamber 108 is formed by the upper portion of the center column side wall 105, the base plate 104 and the upper portion of the outer side wall 109. The toroidal chamber is lined, as shown at 110, with a suitable resilient material such as hard rubber or polyurethane.

The motor is supported in the center column by support rings and a clamp assembly as shown generally at 111, and has upper and lower eccentric weights 112 and 113 attached to either end of the vertical motor shaft. The center column may be provided with a cover 114 which may be affixed to a cylindrical projection 115 of the center column 105. Located across a radius of the toroidal chamber 108 is a vertical dam or weir 116 which, as illustrated, projects below the upper extremity of the lining 110. The weir is retractable through the bottom of the lower mill plate 104 and the lining 110 by an appropriate slot and is arranged to be raised and lowered in the slot by one or more air cylinders 117 and their associated pistons 118. The upper end of the piston 118 is afiixed to the upper surface 119, as illustrated, by the flange 120. The weir 116 is hollow so that when the pistons 118 are retracted into the air cylinder 117, the weir moves downward and covers a portion of the air cylinders 117. The notched portion 121 is to allow the weir to retract to cover the air cylinder support structure 122 so that when the weir 116 is fully retracted, it is approximately level with the bottom mill lining 110. During ordinary finishing operations, the weir 116 is held below its maximum upper level and may be as low as flush with the bottom portion of the mill. When the finishing cycle is completed, air under pressure may be applied to the air inlet hose 123 to force the pistons 118 upwardly so that the weir moves to its uppermost position in the chamber. The height of the weir 116 at its uppermost portion may be controlled by the bracket and stop arrangement 124 and the depending adjustable bracket and lug 125. When the weir is in its uppermost position, the parts and media are caused to climb up the upstream side of the weir and fall on to a screen so that the parts may be separated from the media, the media falling back into the chamber 108 while the finished parts are removed from the apparatus.

In FIGURE 1, the toroidal bowl of a finishing mill is illustrated partially in phantom, the inner circle 11 of the drawing indicating the center column. The exterior wall 12 and interior wall 13 are preferably of metallic construction and are lined on their interior surfaces 14 and 15 with a non-abrasive, non-metallic material such as hard rubber, or, preferably, polyurethane. The interior lining 15 is generally arcuate and follows the circular configuration of the interior wall 13 throughout the diameter thereof except for that portion in the neighborhood of the vertical weir or darn 16. In order to facilitate the vertical upward and downward movement of the weir 16, relatively flat portions 17 and 18 are provided on the linings 14 and 15. As with the interior lining 15, the outer lining 14 follows the curvature of the outer wall '12 except in the portions immediately adjacent and including the weir 16. The fiat portions 17 and 18 of the linings 14 and 15 are provided to reduce binding which might be caused by the movement of the weir 16. As indicated above, it is necessary that the weir move freely up and down in the chamber 19 created by the inner and outer walls 12 and 13 and the curved or flat bottom of the mill (not shown). In practice, the Weir 16 is retractable through an opening provided in the mill bottom and, when the mill is being operated in a finishing cycle, the weir is either partially or totally retracted to below its maximum height. Because the mill is ordinarily charged with an aqueous finishing liquid in addition to the parts and media being processed, it is necessary that the ends of the darn 16 immediately adjacent the linings 14 and 15 seal positively against these linings to prevent the flow of liquid through the bottom opening, and as indicated above, still be freely movable to any desired position vertically in the mill. This is accomplished by forming the ends of the weir in a concave, arcuate shape throughout the length thereof except for the uppermost portion.

When the mill is in operation, the vibratory forces of the eccentric weight motors used to energize the mill cause movement of the mass in the mill in two separate and superimposed patterns. One of these modes of motion causes charge of parts and media to climb up the outer lining 14 and roll inward toward the center Wall 13. The other mode of motion causes the entire mass of parts and media to move generally in the direction of the arrow 20 toward the upstream side 21 of the weir 16. Thus, a considerable force is exerted against the weir and provision must be made to positively retain the weir 16 in its vertical upright position so that it will not bind against the opening in the bottom of the mill through which it projects. This is accomplished by increasing the width of the inner and outer linings 14 and 15 in the areas 22 and 23 to form retaining surfaces 24 and 25 which project outwardly from the linings 14 and 15 immediately downstream of the weir.

The lining portions 22 and 23 which form the retaining surfaces 24 and 25 need not be integral with the chamber linings as shown, but may in the alternative be bolted in or otherwise afiixed separately. They may be of any suitable material so long as they form a retaining surface for the weir 16 to prevent its dislocation by the force of the charge.

Referring now to FIGURE 2, there is shown a vertical cross-section of the weir through the line 22 in FIG- URE l which is taken immediately at the leading or downstream edge of the weir 16. In FIGURE 2, the dashed line 40 represents the arcuate bottom of the lining of the finishing chamber 19 behind the weir when the same is raised to its uppermost vertical position. The view shown in FIGURE 2 is broken away at the linings 15 and 14 and shows the weir 16 having a horizontally extending upper surface 41 with upwardly extending projections 42 and 43 at either extremity. The lower portion of the weir extends below the bottom 40 of the toroidal bowl and provision may be made as indicated by the broken away shafts 44 for moving the weir up and down by means of air cylinders.

FIGURE 3 is an enlarged cross section fragmentary view taken through the line 33 of FIGURE 1 immediately upstream of the line 22 in FIGURE 1 showing a cross section through the weir 16. The embodiment of the invention shown in FIGURE 3 is that in which the weir 16 is made from a hollow, metallic frame, preferably aluminum, so that the weir may move downward into a position over that occupied by the air cylinders which cause its movement, such that when the weir is in its lowermost position the air cylinders and its pistons are disposed within the weir. This construction is comprised of a metallic channel member 61 which forms the hollow weir and which is preferably coated with a non-abrasive resilient polymeric material, preferably polyurethane, as indicated at 62. FIGURE 3 illustrates that at the center of the thickness of the weir 16 only the upwardly extending projections or ears 42 and 43 actually contact the lining walls 14 and 15, at the flat portions 17 and 18. As shown in the fragmentary view of FIGURE 3, the outer ear 43 and the outer wall lining 14 are illustrated. The ear 43 serves to wipe the surface of the wall 14 at the flat portion 18 when the weir moves vertically upward in the mill chamber thereby removing any debris standing in the way of the weir and helping to prevent the weir from binding against the mill wall lining. This arrangement also aids in sealing the weir against the intrusion of any liquid into the slot through which the weir moves. FIGURE 3 also indicates that only the leading and trailing edge of the end of the weir adjacent the lining actually contacts the lining, the inner portions of the edges are spaced away from the flat portion 18 as indicated by the space at 63.

This is more clearly illustrated by FIGURE 4 which is a horizontal cross section in fragment taken through the line 4-4 of FIGURE 3. In FIGURE 4, the flat portion 18 of the lining 14 is shown to be contacted by the weir 16 edge at the points 71 and 72 only. These edge points, 71 and 72, may have small fiat portions at the area of contact with the lining 14. The radial outside edge 73 of the weir 16 (as well as the radial inside edgenot shown) is arcuate in cross section and concave with respect to the mill lining 14. This configuration enables the weir 16 to move more freely up and down and to maintain the weir free of binding against the fiat portion 18 of the lining 14 in the event that foreign matter does penetrate either between the edges 71 and 72 or the ear 43 and the lining wall. FIGURE 4 also indicates the channel member 61 which forms the hollow weir of one embodiment of the invention and the retaining surface 24- formed by widening the lining 14 as shown in FIGURE 1.

The exact configuration of the ear 43 is illustrated in FIGURE 5. As the weir is coated with a resilient material such as polyurethane, it has been found that a more positive seal between the lining and the weir is provided if the ear 43 is fabricated so that when it is not under tension against the mill lining it would have dimensions which would ordinarily make a projection outwardly from the edge of the mill lining. This is illustrated by the line 81 in FIGURE 5 which indicates the interior location of the portion 18 of the lining and the dotted line 82 indicating the outward radial end of the weir 16. As can be seen, the outer edge 83 of the ear 43 projects past the lining edge defined by the line 81. Thus, when the weir works in a vertical direction against the mill lining, there is formed a positive seal by virtue of the resiliency of the coating and lining material.

While particular embodiments of this invention have been shown and described, it is not intended to limit the same to the exact details of the construction set forth and it embraces such changes, modifications and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

What is claimed is:

1. A vibratory apparatus for finishing, polishing, deburring or grinding comprising a base,

a container for receiving a charge of media and parts to be finished, said container forming a generally toroidal channel,

means for resiliently mounting said container on said base,

vibratory means for imparting relatively high frequency vibrations to said container,

weir means associated with said container and arranged generally perpendicular to said channel, said weir means being retractable through the bottom of said channel in a slot provided therein, and

said channel being provided with curb members at the downstream portion of said weir means to hold said weir means in its vertical alignment against pressure from said charge of parts and media while said apparatus is subjected to vibration.

2. A vibratory apparatus for finishing, polishing, de-

burring or grinding comprising a base,

a container for receiving a charge of media and parts to be finished, said container forming a generally toroidal channel,

means for resiliently mounting said container on said base,

vibratory means for imparting relatively high frequency vibrations to said container,

weir means for said container arranged generally perpendicular to said channel, said Weir means being supported for movement into and out of said channel and being retractable through the bottom of said channel in a slot provided therein, and

said channel being provided with curb members at the downstream side edges of said weir means to hold said weir means in its substantially vertical alignment against pressure from said charge of parts and media while said apparatus is subjected to vibration.

3. A vibratory apparatus for finishing, polishing, de-

burring or grinding, comprising a base,

a container for receiving a charge of media and parts to be finished, said container forming a generally toroidal channel, said channel having radially inward and outward sides,

means for resiliently mounting said container on said base,

vibratory means for imparting relatively high frequency vibrations to said container,

weir means for said container arranged generally perpendicular to said channel, said weir means being retractable through the bottom of said channel in a slot provided therein, and

said inward and outward sides of said channel being provided with curb members at the downstream portion of said weir means to hold said weir means in its substantially vertical alignment against pressure from said charge of parts and media while said apparatus is subjected to vibration, said curb mem bers comprising substantially vertical retaining surfaces.

4. A vibratory apparatus for finishing, polishing, de-

burring or grinding, comprising a base,

a container for receiving a charge of media and parts to be finished, said container forming a generally toroidal channel, said channel having radially inward and outward sides,

means for resiliently mounting said container on said base,

vibratory means for imparting relatively high frequency vibrations to said container,

dam means for said container arranged generally perpendicular to said channel, said dam means being retractable through the bottom of said channel in a slot provided therein, and

said inward and outward sides of said channel being provided with curb members at the downstream portion of said dam means to hold said darn means in its substantially vertical alignment against pressure from said charge of parts and media while said apparatus is subjected to vibration, said curb members comprising substantially vertical retaining surfaces.

References Cited UNITED STATES PATENTS HAROLD D. WHITEHEAD, Primary Examiner US. Cl. X.R. 

